Title: SWiss multicenter Intracoronary Stem cells Study in Acute Myocardial Infarction (SWISS-AMI).

Study population: Patients with acute myocardial infarction, treated with primary PCI.

Objective: To determine whether intracoronary infusion of BMCs improves recovery of left ventricular function after acute myocardial infarction treated by PCI

Design: Multi-center, randomized, controlled clinical trial with central core lab analysis for MRI.

Therapy: Intracoronary infusion of BMCs in the infarct related artery at 5-7 days or 3-4 weeks after successful primary PCI

Primary Endpoint: Change in global left ventricular ejection fraction (LVEF) at 4 months relative to baseline measured by quantitative MRI.

Secondary Endpoints:

• Change in LVEF at MRI at 12 months
• Change in regional left ventricular wall motion and thickness at 4 and 12 months.
• Change in infarct size at 4 and 12 months as assessed by "delayed enhancement" technique by MRI
• Analysis of the myocardial infarct size and transmurality, time to PCI and coronary flow characteristics after PCI as predictor of LV remodeling and change after cell therapy
• Change in myocardial perfusion at 4 and 12 months
• Change in serum level of amino-terminal pro-brain natriuretic peptide (NT pro-BNP)
• Major adverse cardiac events (MACE: death, myocardial infarction, TVR (ACBP or PCI, stroke, hospitalization for cardiac reasons) at 12 months

Interventions:

• Aspiration of 50 ml bone marrow (<24 hours) prior to administration
• Intracoronary balloon-based infusion of 10 ml BMCs
• Cardiac MRI at baseline (resp. at hospital discharge), at 4 and 12 months

Therapy groups: Bone marrow-derived stem cells infusion in the successfully revascularized infarct related vessel at day 5-7 or day 21-28.

Control group: Management according to the "state of the art" medical therapy after successful primary PCI.

Safety: A study independent "safety committee" will analyze the clinical results after the first 60 patients.

Inclusion Criteria:

• Visual LVEF at angiogram or echocardiography ≤45%
• Treatment by primary PCI within 24 hours of the onset of chest pain or initial treatment with thrombolysis within the 12 hours followed by PCI within the 24 hours of the onset of chest pain
• Significant regional LV wall motion dysfunction in the infarct related territory
• Age >18 years

Exclusion Criteria:

• Abnormal regional wall motion outside the infarct region
• Known previous myocardial infarction in the same target vessel
• Known pre-existing left ventricular dysfunction (EF<45% prior to admission)
• Need for revascularization in the non infarct-related coronary within 4 months
• Pre-existing symptoms of heart failure or known cardiomyopathy
• Known active infection or chronic infection with HIV, HBV or HCV
• Chronic inflammatory disease
• Serious concomitant disease with a life expectancy of less than one year
• Follow up impossible (no fixed abode, etc)
• Contraindication for cardiac MRI (i.e. pace maker, neurostimulator, claustrophobia)
• Severe renal failure (creatinine >250 mmol/l)
• Relevant liver disease (GOT > 2x norm or spontaneous INR > 1,5)
• Anemia (Hb < 8.5 mg/dl), Thrombocytopenia (<100.000/µl)
• Pregnancy
• Participation at a clinical trial in the last 30 days